Question

Select the incorrect match:
A. Submetacentric chromosomes- L- shaped chromosomes
B. Lampbrush chromosomes- diplotene bivalents
C. Polytene chromosomes- oocytes of amphibians
D. Allosomes- sex chromososmes

Answer 1

Polytene chromosomes are large chromosomes usually found in the interphase of nuclei cells and are giant chromosomes. They are found in Drosophila and the protozoan group of ciliophora.

Complete answer:
(A)The four types of chromosomes based on the position of centromere, metacentric, sub metacentric, acrocentric and telocentric. Sub metacentric chromosomes are located in the middle shape of sub metacentric are L in shape as in these chromosomes one arm is short and the other arm is long.
b) Lampbrush chromosomes are chromosomes found in oocytes of but not in mammals. These are formed during the diplotene stage of meiotic prophase I.
(c) Polytene chromosomes are giant chromosomes. They are commonly seen in two-winged flies their large size showing numerous structures.
(d) Chromosomes are of two types, allosomes and autosomes. Allosomes are sex chromosomes.

Hence, the correct answer is option (C).

Additional information:
Polytene chromosomes are types of interphase chromosomes consisting of thousands of DNA strands.
In the axis of polytene chromosome regions of low and high concentration are found in high concentration known as chromomere bands and low concentration known as intra chromomere.

Note: Polyteny is found in a wide range of organisms, appearing at many stages of evolution. For example, it is seen in Infusoria, which appeared as early as the Precambrian era (more than 600 million years ago), in Collembola, which appeared in the middle of the Mesozoic era (more than 400 million years ago), in Diptera and in mammals (100 million years ago).Polytene chromosomes are found in many tissues of the insects example- Diptera and Collembola